I have a Wista 45DX - The same as your consideration but with modest rear shift. It handles a 90mm lens just fine and can provide plenty of movements (on the front stand). You won't get it to fold up with a 90mm or any other lens unless it is very small and compact, even then, you'd probably want to reverse it before packing up... A common fault on the Wista is badly creased bellows as a result of a user trying to fold it up with a lens attached - You should be able to pick one up for under £400.
Originally Posted by Nomad
I sometimes use a 300mm lens, but it is getting close to the limits of bellows draw - Also not particularly rigid at these limits, but that is the trade off for a lightweight camera. At times, I wish for a Graflok rather than the regular spring back, but that would add to the weight.
One thing to watch for - The ground glass is fragile and very easy to break and nigh on impossible to find a replacement (in the UK). Ended up buying a bulk quantity from a specialist glass supplier as it worked out cheaper than ordering just one from Japan.